I already own a car. An affordable EV is a thing I'll buy in like 15 more years when my already 20 year old Toyota finally dies maybe.
If I bought it sooner, then my car would just go into the second hand market and do the same thing.
"Affordable" isn't changing anything: I don't need another car, and I'm not going to prematurely crush mine into a cube.
I drive very little, so having a fossil car sitting in the drive is more carbon efficient than buying a new EV that had to be built and shipped.
Somone who drives a lot may be able to scrap their fossil car, buy a new EV and start saving on carbon emissions in a much shorter time than me.